Of white lead by precipitation



2 Sheets-Sheet 1.

R. BAKER. Making White Lead.

' Patented Apr. 3, 1855.

2 Shee t sSheet 2.

R. BAKER.

Making White Lead.

Patented Apr. 3, 1855.

AM. PHOTO'LITHQCQNX. (DSBORNE'S PROCESS) rrnnsrarns jRIoHAnD BAKERQOF NERK, NEW JERSEY.

To all tb hom it maye emf \lfBe'tknowntht I,RIQI-IARD B KER, of the cityof Newark, in the county of Essex andYState'ofNewJersey; have invented anew; and" Improved .Mode fof Making Car bonateofLead with aratusAdapted.toj thef-Purpose, commonly called White Leadzfiland Ifdo. herebyjfdeclare thatthe ffollowing is fulland exact. description thereof,referencebeinghadto the accompanying drawings and to. the lettersmarkedIfthereon. p

. \TheVnature of my. invention consists in controlling theapplicationofthe carbonics acidgas necessaryftol decompose the subxacetate.ofpleadjin forming carbonateof lead hy precipitation, iwith anfapparatus by which fthecarbonate acid' gas is all .used, in-

Samaralarge portionbeing lostas in the 1 oldway thereby rendering theprecipita process too expensive, notwithstanding a moresuperiorcarbonate of lead can be @deb precipitationythan by the Common bonic acid gas, mixing 1 the solutions, apply.- l si h ps wndc p e na t er ce formingthe carbonatgready to be'Washed tionahg elevatidn showingthe internal arrangement of the parts. g p I s no new i methdofgenerat-ing the gas, iQr-HQn wjm r t he e u d, in P ducing thecarbonic acid gas,;or the subacetate of lead it is deemed unnecessary tohei fi mP iQIt asf hey r ll y H otthosefjconv sant"with.n1aking a fb Caidae .w l as o ate ad; T ey w l ib $P 1 6ff nly nnected with" the apparae pilrpq eii tthe i Figsfll and L 2 he plancomplete. Like letters refepartsQandfpurposes throughoutthe r gs.fLarge let- :minor parts of i theapparatus,

. arr on: the vljnizzingja and settling of the solutionas onecanfibeflcharged and set to I lthese vessels are placedwater, sugar oflead, and protoxid'y-of Qjlead properly protug, erein described,

, poiitioned. {The thickeru part is allowed to settle, the clear liquidsolutionis drawn oflhthrough the faucets aria and conducted by i ICE, 1

A NUEAC U E or" WHITE LEAD BY PBECIIITA'I'ION..

B. The solution is sub-acetate of. lead at this stage ofthe proceeding.It is pumped iup the pump. and conveyed by i the ipipesc 0 into theprecipitator D which is isready tobe acted upon by the carbonic gas. Theprecipitator-isclosed to prevent leakage. In the generator E is placed,carbonate of lime orpchalk, and water. In the top of this generatorisplaced a small ;vessel Li to. hold sulfuric acid, having a smallholein the side, opening into the gen- 1 erator. In the upper part ofthissmall vessel, is. placed a solid plunger 6 attached-to a screwpassing through a nut in the top of the same. By means of thisscrew, theplunger, can be depressed by degrees, which throughthe hole inthe side,and drop on the lime. It. is necessary to apply the acid slowly, and insmall quantities, in orderto tonot" produce a dangerous pressure, The.

;vessel through a hole in the top which is stopped with a screw stopper,as the pressure of thelgas would be likely to blow out end, blades 9, soarranged as to extend to nearfthe side of the generator. On the upperpart of this shaftgis a screw which works in a suitable nutin the top ofthe acid andlime, which with the elevation and depression produced bythe screw, facilitates the operation, producing a larger quantity ofgas,with less waste than otherwise. The

and soon down into the water j in thewash ivessel K, here'it iswashedby' a smalllquanjtity of water,and rises up into the upper part oftheyvessel K and thence through the pipe 1 and into the vessel D. Thepipe Z is intended merely to pass through the head of; the vessel D andnot to come in contact with the solution as the gas rises up through thepipe Z and collects in the space m and n n throughthe force pump G andby its actionisforced. through the tube 0 and its branches,intothesolution to allow the solul the pipes b, 6, down into the pump cistern@causes a small quantity of the acid, to pass" give the lime, time toabsorb the acid, so as an ordinary stopper. To facilitate thedecomposition of the lime, Iuse an agitator f i beinga vertical shaftfixed in the center of the generator, havingattached to its lowergeneraton'at the top is placed a crank l2; to 1 revolve the blades, thusmixing the sulfuric gas rises upandpasses through the pipe z from thisspaceis drawn through the pipev -filled to near the top with thesolution, and

sulfuric acid is introduced into thesmall tion to absorb a portion, thebalance rising and being operated upon again in the same manner, untilthe solution has absorbed all it can; thus becoming decomposed, andproducing carbonate of lead.

The several stages of the process are known, and determined by the aidof the hydrometer, and known chemical equivalents, which can becalculated sufiiciently correct, to insure success.

I prefer applying the carbonic acid gas to the solution, in preferenceto applying the solution to the gas by shower or otherwise, as time isnecessary for the solution. to absorb the gas. It also thickens, and hasa tendency to foam, which also makes it difiicult to apply to the gas,besides the effect is not so good. After the complete decomposition ofthe solution, the carbonate of lead is precipitated to the bottom, andleaves the clear liquid acetate of lead to be drawn off through thefaucets near the bottom, (hid in the drawing by the leader,) forremoving the carbonate, and conveyed through the pipe seen in Fig. 2into the pump cistern B and is pumped up into the solution vessels A Aand is ready to be recharged for the next operation. The carbonate oflead is drawn out of the precipitator, at the opening 7' r and isconducted through the pipe 8 8 into the receiving vessel H, where it isleft for the mother water to withdraw from the carbonate and the fluidis drawn off from time to time as the progress of the separation willpermit, through the faucets t t &c. It is then ready for the washing.The neutral salts being all washed out. After this it is dried verygradually in order to prevent discoloration. To soften the carbonate, alittle saleratus is used in the washing.

The residuum which will collect in time in the solution vessels A A canbe removed, by a hot solution of sugar of lead, and water which willdissolve the protoxid of lead, which will permit the same to be drawnoff into the pump cistern below, and be used in the next process. Theresiduum in the generator when exhausted is tobe removed through theaperture u and may be used for some other purpose, as it is of nofurther use, in generating carbonic, acid gas. The generator E washingvessel K precipitator D and pump C including their connections, are allclosed, to prevent the leakage of the carbonic acid gas, that none belost by exposure to the atmosphere I I I are the stands and floor, bywhich the appa-- ratus is supported.

There is to be attached to the apparatus an airtight gas bag orexpansion balloon furnished with a stop cock (which has hitherto beenomitted in the specification and is moreover an essential part of theapparatus). The stop cock of the balloon is to be screwed into the headof the precipitator or vessel D in any convenient part thereof. Theballon may be suspended from the ceiling of the room. The use of theballoon is to collect and retain the carbonic acid gas until entireabsorption has taken place, be ing in communication with the space we inthe vessel D) when it will return from an inflated to a collapsedcondition, showing very accurately the rate of absorption. The use ofthe stop cock is to shut off the communication between the balloon andprecipi tator or vessel D, as in case, of accident or leakage the gasmay be sustained in the balloon until any difliculty is adjusted.

What I claim as my invention, and desire to secure by Letters Patent,is-- 1. An improvement in the combination of apparatus so arranged andconstructed as to produce carbonate of lead by precipitation. moreexpeditiously and economically than by any other arrangement heretoforeused for the same purpose.

I do not claim each and every part of the apparatus herein described asnew, I claim connecting with an air pump a series of verticaldistribution pipes 0 0 0 as herein described in specification consistingof a great many in number descending vertically from the main horizontalpipe 0 and passing down through the head of the precipitating vesselD-into the solution of subacetate of lead 1 pipe at least through eachsquare foot of surface of .the top of the precipitating vessel therebytraversing the solution with a great number of small jets or blasts ofcarbonic acid gas causing a very rapid decomposition of the solution asthe vertical pipes cannot choke up with the ponderous precipitate aconstant blast from each pipe is thereby insured.

RICHARD BAKER. Witnessed in the presence of JARVIS B. AYREs, A, L. Arms.

